[inspectorudy]

The simplest thing to do is to bypass everything with a jumper cable and see if the PTO stays engaged. I just had to do that with my starter not engaging when the key was turned. It turned out the little 20 amp fuse had crud on one end and was only allowing 6.5 volts to the solenoid. Hook up a jumper wire to a hot 12 volt source, disconnect the connector in the front at the PTO and hook up the jumper to it. Then with the mower running touch and hold the 12 v source and see if it stays on. If it does then you just work back one element in the circuit at a time until you get to the culprit. On my 1811 I have already found two connectors that had corroded terminals in them but looked fine from the out side. Good luck.